JP2018149841A - Knee airbag and knee airbag device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a knee airbag which enables improvement of restraining force for restraining occupant's lower leg parts while keeping impact absorption force for absorbing impact to the occupant's lower leg parts, and to provide a knee airbag device.SOLUTION: A knee airbag device includes: a knee airbag 2 which is inflated and expanded between a dash board and occupant's lower leg parts; and an inflator which supplies a gas to the knee airbag 2. The knee airbag 2 includes: an upper expansion part 21 disposed at a position that may contact with occupant's knees; and a pair of groove parts 22 which are disposed at positions that may contact along occupant's shanks and having a shape recessed relative to the upper expansion part 21.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a knee airbag and a knee airbag device, and more particularly, to a knee airbag and a knee airbag device suitable for restraining an occupant's lower leg.

  A vehicle such as an automobile may be provided with a knee airbag device for absorbing an impact generated in the occupant's leg (portion including knee and shin) at the time of a vehicle collision. Such knee airbag devices are generally arranged on a dashboard, which is an interior cover in front of the occupant's knees, and are configured to inflate and deploy the airbag between the dashboard and the occupant when the vehicle collides. In such a knee airbag device, it has already been proposed to partition the airbag into a plurality of inflating portions using a connecting member such as a tether (see, for example, Patent Document 1 and Patent Document 2).

  For example, in the knee airbag device described in Patent Document 1, while the airbag is partitioned so as to be multi-staged in the vertical direction, the longitudinal tether is disposed at a position where both knees contact each other, so The depression which restrains is formed. Further, in the knee airbag device described in Patent Document 2, both the knees of the occupant are restrained by partitioning the airbag so as to be multi-staged in the lateral direction and turning the outer inflating part around the outer sides of both knees. I am doing so.

Japanese Patent No. 5786951 Japanese Patent No. 4231520

  However, in the knee airbag devices described in Patent Document 1 and Patent Document 2, in order to constrain the occupant's knees, a depression having a smaller expansion thickness than other portions is formed. There is a problem that the impact absorbing power in the dent becomes weaker than other portions. Therefore, when the airbag is designed based on the shock absorbing ability with respect to the occupant's knee, there is a problem that the airbag becomes large, or a problem that the concavity becomes shallow and the restraining force of the lower leg is reduced. Will result.

  Further, as in the knee airbag device described in Patent Document 1, when an inflatable portion (so-called lateral cell) extending in the lateral direction is disposed at a position where the occupant's shin contacts, There is also a problem that the shin portion easily moves in the lateral direction when the bag contacts the airbag.

  The present invention has been devised in view of the above-described problems, and a knee airbag and a knee that can improve the restraining force of the occupant's lower leg while maintaining the impact absorbing force against the occupant's lower leg. An object is to provide an airbag device.

  According to the present invention, in a knee airbag that is inflated and deployed between a dashboard and an occupant's lower leg, an upper inflatable portion disposed at a position where the knee can be in contact with the occupant's knee, and the occupant's shin And a pair of grooves having a recessed shape with respect to the upper inflating portion. The knee airbag is provided.

  Further, according to the present invention, in a knee airbag device comprising a knee airbag inflated and deployed between a dashboard and a lower leg of an occupant, and an inflator for supplying gas to the knee airbag, The knee airbag has an upper inflatable portion disposed at a position where the knee airbag can come into contact with the occupant's knee, and a recessed shape with respect to the upper inflatable portion which is disposed at a position where the knee airbag can come into contact with the shin of the occupant. And a pair of grooves having a knee airbag device.

  In the knee airbag and the knee airbag device described above, the knee airbag includes a front panel disposed on the occupant side and a rear panel disposed on the dashboard side, and the pair of grooves includes the pair of grooves, You may be comprised by a pair of 1st tether which connects a front panel and the said rear panel.

  The first tether may include both end portions sewn to the rear panel and an intermediate portion sewn to the front panel.

  The knee airbag may include a second tether that is disposed above an intermediate portion of the pair of first tethers and connects the front panel and the rear panel.

  The knee airbag may include a third tether that is disposed below the pair of first tethers and connects the front panel and the rear panel.

  Further, the knee airbag includes a central inflating portion that is defined by the groove portion and disposed between the shins of the occupant, an outer inflating portion that is disposed on a window side of the central inflating portion, and the central inflating portion. An inner inflatable portion disposed on the vehicle body center side than the portion, and the central inflatable portion may have a larger capacity than the outer inflatable portion and the inner inflatable portion.

  Furthermore, the outer expansion part may have a larger capacity than the inner expansion part.

  Further, the knee airbag is, for example, a knee airbag disposed in a driver's seat.

  According to the knee airbag and knee airbag device according to the present invention described above, the occupant collided with the knee airbag by arranging the upper inflating portion that abuts the occupant's knee and the groove portion that abuts the occupant's shin. The impact of the knee at the time can be absorbed by the upper inflating part, and the shin can be restrained by the depression of the groove part. Therefore, according to the present invention, it is possible to improve the restraining force of the occupant's lower leg while maintaining the shock absorbing force against the occupant's lower leg.

It is sectional drawing which shows the knee airbag apparatus which concerns on one Embodiment of this invention, (A) has shown the state before expansion | deployment and (B) has shown the state after completion of expansion | deployment. It is a perspective view which shows the knee airbag after completion of inflation and deployment. It is a plane development view of the base fabric which constitutes a knee airbag. It is a figure which shows the tether arrange | positioned at a knee airbag, (A) is the 1st tether which divides an outer side expansion part, (B) is the 1st tether which divides an inner side expansion part, (C) is a 2nd tether, (D) shows the third tether. It is a figure which shows the knee airbag after completion | finish of inflation deployment, (A) is a front view, (B) is a rear view. It is sectional drawing of the knee airbag shown in FIG. 5, (A) is AA sectional view, (B) is BB sectional drawing, (C) shows CC sectional drawing. Yes.

  Embodiments of the present invention will be described below with reference to FIGS. 1 (A) to 6 (C). Here, FIG. 1 is a cross-sectional view showing a knee airbag device according to an embodiment of the present invention, in which (A) shows a state before inflation and deployment, and (B) shows a state after completion of inflation and deployment. Yes. FIG. 2 is a perspective view showing the knee airbag after completion of inflation and deployment.

  A knee airbag device 1 according to an embodiment of the present invention is a knee airbag that is inflated and deployed between a dashboard D and a lower leg portion of an occupant M, as shown in FIGS. 2 and an inflator 3 that supplies gas to the knee airbag 2. The knee airbag 2 includes an upper inflatable portion 21 that is disposed at a position where the knee airbag 2 can contact the knee Mk of the occupant M, and a shin of the occupant M. And a pair of grooves 22 having a shape recessed with respect to the upper inflatable portion 21.

  In addition, in FIG. 1 (A) and FIG. 1 (B), the state which notched a part of dashboard D is shown in figure. A knee airbag 2 shown in FIG. 1B is a cross-sectional view of a substantially central portion of the knee airbag shown in FIG.

  Dashboard D is a general term for all interior parts arranged in front of a front seat of a vehicle. On the floor surface below the dashboard D, an operation pedal (accelerator pedal or brake pedal) and a footrest are arranged. When the occupant M gets on, the lower leg is arranged between the floor and the dashboard D. The lower leg part is a part including the knee Mk and the shin Ms. Further, as shown in FIG. 1A, a steering wheel S and a steering column C are disposed on the surface of the dashboard D on the occupant M side in the driver's seat.

  The inflator 3 has, for example, a substantially cylindrical outer shape, and a gas outlet is formed in a portion enclosed in the knee airbag 2. The inflator 3 is connected to an ECU (electronic control unit) (not shown) and is controlled based on measurement values of an acceleration sensor or the like. When the ECU detects a vehicle collision, the chemical stored in the inflator 3 is burned to generate gas, and the gas is supplied to the knee airbag 2.

  The inflator 3 and the knee airbag 2 are accommodated and fixed in a box-shaped retainer 4 as shown in FIG. 1A, for example. The retainer 4 is fixed to an in-vehicle structure disposed in the dashboard D via a bracket or the like. Further, the dashboard D located on the front surface of the retainer 4 is formed with a thin portion (tea line) that tears the dashboard D when the knee airbag 2 is inflated and deployed.

  For example, as shown in FIG. 2, the knee airbag 2 is in an inflated and deployed state, an upper inflating portion 21, a pair of groove portions 22, and a central inflating portion 23 disposed in the middle of both shins Ms of the occupant M. And an outer expansion portion 24 disposed on the window side of the central expansion portion 23, an inner expansion portion 25 disposed on the vehicle body central side of the central expansion portion 23, and a lower expansion disposed below the central expansion portion 23. Part 26. The compartments of these inflating parts are formed by a tether that constitutes the groove part 22 as will be described later.

  The upper inflating portion 21 of the knee airbag 2 shown in FIG. 2 includes a pair of convex portions 21a formed at positions where the knee Mk of the occupant M can be contacted, and an intermediate portion 21b communicating with the pair of convex portions 21a. It is equipped with. The illustrated intermediate portion 21b is formed to have an expansion thickness smaller than that of the convex portion 21a, but may have the same expansion thickness as the convex portion 21a.

  The knee airbag 2 is formed such that the central inflatable portion 23 has a larger capacity than the outer inflatable portion 24 and the inner inflatable portion 25, and the outer inflatable portion 24 has a larger capacity than the inner inflatable portion 25. Yes. For example, in the case of a left-hand drive with a right-hand drive vehicle or a right-hand drive with a left-hand drive vehicle, the driver (occupant M) puts his / her foot on the operation pedal or footrest when there is an offset frontal collision with a vehicle on the opposite lane. In many cases, the inventors have learned that the crus tend to move to the window side and the ankle tends to be twisted through intensive studies by the inventors.

  Therefore, in the knee airbag 2 arranged in the driver's seat, the capacity of the outer inflating part 24 arranged on the window side is made larger than the capacity of the inner inflating part 25 arranged on the vehicle body center side. Since the central inflating part 23 is arranged at the middle part of both feet of the occupant M, the surface area tends to be large. As a result, the capacity of the central inflating part 23 is larger than the capacity of the outer inflating part 24. Therefore, the knee airbag 2 has a relationship of the capacity of the inner inflating portion 25 <the capacity of the outer inflating portion 24 <the central inflating portion 23.

  Here, FIG. 3 is a plan development view of the base fabric constituting the knee airbag. 4A and 4B are diagrams showing a tether disposed on the knee airbag, in which FIG. 4A is a first tether that defines an outer inflatable portion, and FIG. 4B is a first tether that defines an inner inflatable portion. ) Shows the second tether, and (D) shows the third tether. In addition, the dotted line shown in FIG.3 and FIG.4 (A)-FIG.4 (D) has each shown the stitching | suture planned line.

  The base fabric constituting the knee airbag 2 is, for example, one sheet provided with a front panel 2f disposed on the passenger M side and a rear panel 2r disposed on the dashboard D side as shown in FIG. It is a base fabric. Such a base fabric is folded along a fold line L indicated by a one-dot chain line in the drawing, and is formed into a bag shape by sewing the edge of the folded portion along the planned stitching line 2s.

  The front panel 2f and the rear panel 2r have, for example, a substantially hexagonal shape combining a rectangle and a trapezoid, and the lower lateral width in which the inflator 3 is disposed is narrow, and the upper lateral width in which the upper inflating portion 21 is disposed. It is formed to be wide. In addition, the surrounding line shown with the dashed-two dotted line in the figure has shown the location (inflator arrangement | positioning plan part 3p) which arrange | positions the inflator 3. FIG.

  As shown in FIGS. 4 (A) and 4 (B), the pair of grooves 22 is constituted by an outer first tether 5 and an inner first tether 5 ′ that connect the front panel 2f and the rear panel 2r. The outer first tether 5 and the inner first tether 5 'include, for example, both end portions sewn to the rear panel 2r and an intermediate portion sewn to the front panel 2f.

  Specifically, the outer first tether 5 shown in FIG. 4 (A) includes stitching planned lines 5a and 5b sewn to the rear panel 2r, and a stitching planned line 5c sewn to the front panel 2f. Yes. Here, the stitching planned lines 5a and 5b are set in a straight line, and the stitching planned line 5c is set in an annular shape, but is not limited to this configuration. The planned stitch line 5a is stitched to the planned stitch line 5a shown in FIG. 3, the planned stitch line 5b is stitched to the planned stitch line 5b shown in FIG. 3, and the planned stitch line 5c is shown in FIG. The stitched line 5c is sewn.

  Further, the inner first tether 5 'shown in FIG. 4 (B) has stitching planned lines 5a' and 5b 'sewn to the rear panel 2r, and a stitching planned line 5c' sewn to the front panel 2f. doing. Here, the planned stitching lines 5a ′ and 5b ′ are set in a straight line, and the planned stitching line 5c ′ is set in an annular shape, but the configuration is not limited thereto. Further, the planned stitch line 5a ′ is sewn to the planned stitch line 5a ′ shown in FIG. 3, the planned stitch line 5b ′ is stitched to the planned stitch line 5b ′ shown in FIG. 3, and the planned stitch line 5c ′ is , And is sewn to the suture line 5c ′ shown in FIG.

  The outer first tether 5 shown in FIG. 4 (A) and the inner first tether 5 ′ shown in FIG. 4 (B) are configured to expand in a substantially V shape when the knee airbag 2 is inflated and deployed. However, it is not limited to such a configuration. For example, the outer first tether 5 and the inner first tether 5 ′ may be configured by cutting an intermediate portion of the illustrated tether, or may be configured by a single tether that expands into an I-shape when inflated and deployed. Also good.

  Although the illustrated outer first tether 5 and inner first tether 5 'have a panel shape with a certain width, the groove portion can be obtained by using a plurality of narrow strip-like or string-like tethers. 22 may be formed.

  As shown in FIG. 4C, the knee airbag 2 is disposed above the pair of first tethers (the outer first tether 5 and the inner first tether 5 ′), and includes a front panel 2f and a rear panel 2r. You may provide the 2nd tether 6 to connect. Specifically, the second tether 6 includes a planned stitch line 6a sewn to the front panel 2f and a planned stitch line 6b sewn to the rear panel 2r.

  Further, the planned stitching line 6a is stitched to the planned stitching line 6a shown in FIG. 3, and the planned stitching line 6b is stitched to the planned stitching line 6b shown in FIG. The second tether 6 may include a plurality of openings 6c through which gas passes. The illustrated second tether 6 has a panel shape having a certain width, but a plurality of narrow strip-like or string-like tethers may be used.

  Further, the distance Ha from the folding line L of the planned sewing line 6a sewn to the front panel 2f may be set smaller than the distance Hb from the folding line L of the planned sewing line 6b sewn to the rear panel 2r. . With this configuration, the intermediate portion 21b of the upper inflatable portion 21 can be bent toward the rear panel 2r during inflation and deployment.

  As shown in FIG. 4D, the knee airbag 2 is disposed below the pair of first tethers (the outer first tether 5 and the inner first tether 5 '), and the front panel 2f and the rear panel 2r are connected to each other. You may provide the 3rd tether 7 to connect. The third tether 7 includes, for example, both end portions sewn to the rear panel 2r and an intermediate portion sewn to the front panel 2f.

  Specifically, the third tether 7 includes stitched lines 7a and 7b stitched to the rear panel 2r, and a stitched line 7c stitched to the front panel 2f. Although the planned stitching lines 7a and 7b are set in a straight line and the planned stitching line 7c is set in an annular shape, the present invention is not limited to such a configuration.

  The planned stitching line 7a is stitched to the planned stitching line 7a shown in FIG. 3, the planned stitching line 7b is stitched to the planned stitching line 7b shown in FIG. 3, and the planned stitching line 7c is shown in FIG. The stitched line 7c is sewn. The third tether 7 may include a plurality of openings 7d through which gas passes.

  The third tether 7 shown in FIG. 4D is configured to expand in a substantially V shape when the knee airbag 2 is inflated and deployed, but is not limited to this configuration. For example, the third tether 7 may be configured by cutting an intermediate portion of the illustrated tether, or may be configured by a single tether that expands into an I shape when inflated and deployed. Although the illustrated third tether 7 has a panel shape with a certain width, a configuration using a plurality of narrow strip-like or string-like tethers may be used.

  Here, FIG. 5 is a view showing the knee airbag after completion of the inflation and deployment, where (A) is a front view and (B) is a rear view. 6 is a cross-sectional view of the knee airbag shown in FIG. 5, in which (A) is a cross-sectional view taken along line AA, (B) is a cross-sectional view taken along line BB, and (C) is a cross-sectional view taken along line CC. , Shows. Note that the front view shown in FIG. 5A and the rear view shown in FIG.

  As described above, the knee airbag 2 includes the outer first tether 5, the inner first tether 5 ′, the second tether 6 and the third tether 7 shown in FIGS. 4 (A) to 4 (D). It is formed by stitching the panel 2f and the rear panel 2r and stitching the edges of the front panel 2f and the rear panel 2r.

  When the inflator 3 is actuated at the time of a vehicle collision and gas is supplied to the knee airbag 2, the inflator 3 is inflated and deployed in the shape shown in FIGS. 5A and 5B, and the upper inflatable portion 21 and the groove portion 22. The central expansion portion 23, the outer expansion portion 24, the inner expansion portion 25, and the lower expansion portion 26 are formed. At this time, the knee Mk of the occupant M comes into contact with the position indicated by the one-dot chain line circle in FIG. 5A, and the shin Ms of the occupant M comes into contact with the position shown by the one-dot chain line.

  In FIG. 6A, the outer inflating portion 24 is constituted by a bifurcated inflating portion that is inflated adjacent to the central inflating portion 23 by the outer first tether 5. In FIG. 6A, the inner inflatable portion 25 is constituted by a bifurcated inflatable portion that is inflated adjacent to the central inflatable portion 23 by the inner first tether 5 ′. The pair of groove portions 22 is formed on the front panel 2 f side adjacent to the central expansion portion 23.

  As shown in FIG. 5 (A), since the second tether 6 is arranged in the middle part of the convex part 21a constituting the upper inflating part 21, it is shown in FIG. 6 (B) and FIG. 6 (C). As described above, the expansion thickness Db of the intermediate portion 21b constituting a part of the upper expansion portion 21 is smaller than the expansion thickness Da of the convex portion 21a.

  Further, the stitching portion (scheduled stitch line 6a) on the front panel 2f side of the second tether 6 is set at a position higher than the stitched portion (scheduled stitch line 6b) on the rear panel 2r side. The intermediate portion 21b of the upper inflatable portion 21 can be bent toward the rear panel 2r side (dashboard D side) at the time of inflating and deploying. For example, the knee airbag 2 is inflated and deployed along an obstacle such as the steering column C. Can do.

  Further, by disposing the second tether 6, the capacity of the intermediate portion 21b of the upper inflating portion 21 where the knee Mk of the occupant M is not in direct contact can be reduced, and the knee airbag 2 can be reduced in size. You can also. The second tether 6 can be omitted as necessary.

  Further, as shown in FIG. 6 (B), the knee airbag 2 can be bent by arranging the third tether 7, and as shown in FIG. The knee airbag 2 released into the vehicle from the retainer 4 disposed inside the surface can be inflated and deployed along the inclined surface of the dashboard D. The shape and arrangement of the third tether 7 are not limited to the illustrated configuration as long as the knee airbag 2 can be bent.

  According to the knee airbag 2 and the knee airbag device 1 according to the above-described embodiment, the occupant M is provided by disposing the upper inflating portion 21 having a sufficient inflating thickness at a location that abuts on the knee Mk of the occupant M. Can sufficiently absorb the impact of the knee Mk when it collides with the knee airbag 2. On the other hand, the movement of the shin Ms when the occupant M collides with the knee airbag 2 is constrained by disposing the groove 22 having a recess covering the front surface of the shin Ms at a position where the occupant M abuts on the shin Ms. Can do.

  In the knee airbag 2 according to the above-described embodiment, the case where the front panel 2f and the rear panel 2r are configured by a single base fabric has been described, but two bases separated into the front panel 2f and the rear panel 2r are described. You may make it comprise with cloth.

  In the knee airbag device 1 according to the above-described embodiment, the case where the knee airbag device 1 is disposed in the driver's seat has been described. However, the knee airbag device 1 may be disposed in the passenger seat. In addition, when the knee airbag device 1 according to the present embodiment is arranged in the passenger seat, the feet of the occupant M are normally placed on the floor of the vehicle body, so compared with the occupant M in the driver seat. The lower leg is considered to be difficult to move left and right. Therefore, when the knee airbag device 1 according to the present embodiment is disposed in the passenger seat, the outer inflation portion 24 and the inner inflation portion 25 of the knee airbag 2 may be set to the same capacity.

  The present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 1 Knee airbag apparatus 2 Knee airbag 2f Front panel 2r Rear panel 3 Inflator 3p Inflator arrangement planned part 4 Retainer 5 Outer first tether 5 'Inner first tether 5a, 5a', 5b, 5b ', 5c, 5c', 6a , 6b, 7a, 7b Scheduled stitch line 6 Second tether 6c, 7d Opening 7 Third tether 21 Upper expansion portion 21a Protruding portion 21b Intermediate portion 22 Groove portion 23 Central expansion portion 24 Outer expansion portion 25 Inner expansion portion 26 Lower expansion portion C Steering column D Dashboard S Steering wheel M Crew Mk Knee Ms Shin

Claims (9)

In the knee airbag that is inflated and deployed between the dashboard and the lower leg of the occupant,
An upper inflatable portion disposed at a position capable of contacting the occupant's knee;
A pair of grooves having a shape recessed with respect to the upper inflating portion, disposed at a position that can be contacted along the shin of the occupant;
A knee airbag characterized by comprising.   A front panel disposed on the occupant side, and a rear panel disposed on the dashboard side, and the pair of grooves are configured by a pair of first tethers connecting the front panel and the rear panel. The knee airbag according to claim 1.   The knee airbag according to claim 2, wherein the first tether includes both ends sewn to the rear panel and an intermediate portion sewn to the front panel.   The knee airbag according to claim 2, further comprising a second tether disposed above the pair of first tethers and connecting the front panel and the rear panel.   The knee airbag according to claim 2, further comprising a third tether disposed below the pair of first tethers and connecting the front panel and the rear panel.   A central inflating portion that is defined by the groove and disposed between the occupants' shins, an outer inflating portion that is disposed on the window side of the central inflating portion, and a vehicle body central side of the central inflating portion 2. The knee airbag according to claim 1, wherein the central inflatable portion has a larger capacity than the outer inflatable portion and the inner inflatable portion.   The knee airbag according to claim 6, wherein the outer inflating portion has a larger capacity than the inner inflating portion.   The knee airbag according to claim 1, wherein the knee airbag is a knee airbag disposed in a driver's seat. In a knee airbag device comprising a knee airbag that is inflated and deployed between a dashboard and an occupant's lower leg, and an inflator that supplies gas to the knee airbag,
The knee airbag device according to any one of claims 1 to 8, wherein the knee airbag is the knee airbag described in any one of claims 1 to 8.